There is conventionally known a semiconductor light-emitting device having a pair of pad electrodes provided on the same side. For example, Patent Document 1 discloses a semiconductor light-emitting device having a pair of pad electrodes provided on an upper surface of a rectangular semiconductor light-emitting device in a plan view. One of the pad electrodes of this semiconductor light-emitting device is provided near one short side of the semiconductor light-emitting device. The other pad electrode is located near the other short side thereof and formed to occupy about two-thirds of the upper surface of the semiconductor light-emitting device.
In this semiconductor light-emitting device, when a voltage is applied between the paired pad electrodes, electrons and holes are injected into a semiconductor layer via the both pad electrodes. The injected electrons and holes recombine in the semiconductor layer, thereby emitting light.
Furthermore, there is conventionally known a semiconductor light-emitting device including a semiconductor layer made of a GaN-based semiconductor and a reflecting layer for reflecting light from a light-emitting layer.
For example, Patent Document 2 discloses a semiconductor light-emitting device including an n-type semiconductor layer, a light-emitting layer, a p-side electrode, an insulating film, a reflecting layer, a p-side pad electrode, and an n-side electrode, and made of a GaN-based semiconductor. The p-side electrode is constituted by a laminated metal structure thin enough to be able to transmit light, and is formed on the p-type semiconductor layer in a state of being ohmic-connected to the p-type semiconductor layer. The insulating film is formed onto the p-side electrode in a state of being partially opened so as to expose a part of the p-side electrode. The reflecting layer is formed on the insulating film in a state of being connected to an exposed portion of the p-side electrode. The p-side pad electrode is formed on a part of the reflecting layer.
In the semiconductor light-emitting device of Patent Document 2, when a forward voltage is applied, electrons are then injected into the n-side electrode and holes are injected into the p-side pad electrode. The injected electrons are injected into the light-emitting layer via the n-type semiconductor layer. The injected holes are injected into the light-emitting layer via the reflecting layer, the p-side electrode, and the p-type semiconductor layer. The electrons and holes injected into the light-emitting layer recombine, thereby emitting blue or green light. Out of the emitted light, the light traveling in a direction of the p-side electrode transmits through the p-side electrode and the insulating film, and then reaches the reflecting layer. The light is reflected by the reflecting layer, changes the traveling direction, again transmits through the p-side electrode and the insulating film, and is irradiated to the outside.    [Patent Document 1] Japanese Patent Application Laid-open No. H7-263754    [Patent Document 2] Japanese Patent Application Laid-open No. 2003-224297